Rear Main Oil Seal

[latvius]

Good question, I don't have an answer for ya.

 

[Larryjb]

I was planning to go ahead and do the rear main seal anyway since I have the time. The I looked at the prices of Dexron VI up here in Canada:

1 qt ACDelco 10-9243 Dexron VI is $29.00 Cdn. That would be $20 USD currently.
RockAuto has it for $4.11 USD, but won't ship fluids to Canada.

I'll still go ahead with the the oil pan seal.

 

[Larryjb]

As I prepare to do the oil pan gasket, I now am wondering what sealant I should use for the corners?

 

[latvius]

Permatex 85080 Ultra Black Maximum Oil Resistance RTV Silicone Gasket Maker, 9.5 oz. PowerBead Can

https://www.amazon.com/gp/product/B000HBGI1M/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

 

[Larryjb]

I started the oil pan gasket job. Everyone seems to avoid dropping the front diff entirely. It seems that all you need to do is remove an electrical connector, vent hose, and the bolts securing the diff to the axles in addition to the mounting bolts for the diff. That can't be that hard to do when compared to the mounting bolts for the diff. At least one of those looks nasty to get at.

So I plan to drop the diff to give me more room.

 

[Larryjb]

Here's what I've done so far:

1. Support vehicle on 4 jack stands.
2. Remove both front wheels (22 mm works well, actually fits better than the imperial).
3. Remove skid plate (18 mm)
4. Drain oil
5. Remove cross member (2 short, 2 long bolts) (forgot to note size, probably 18 mm)
6. Drain front differential fluid (yellow colour, quite clean! ) (13 mm drain bolt, 15 mm fill bolt)
7. Mark axle/differential flange with chalk.
8. Mark front drive shaft.
9. These next eight steps did not have to be done, but I did them planning to remove the front differential entirely:
10. Remove transfer case splash shield (possibly unnecessary)
11. Place transmission in drive and release parking brake (possibly unnecessary)
12. Rotate front drive shaft to remove boot clamp. (possibly unnecessary)
13. Set parking brake. (possibly unnecessary)
14. Remove 2 drive shaft bolts (11 mm) (possibly unnecessary)
15. Release parking brake, rotate drive shaft 180°, reset parking brake (possibly unnecessary)
16. Remove last two drive shaft bolts. (possibly unnecessary)
17. Remove drive shaft from front differential, support with bungee cord. (possibly unnecessary)
18. Return transmission to Park.
19. Remove electrical connector to front differential.
20. Open electrical wire loom clamp on top of differential to release wire.
21. Remove vent hose.
22. Remove 6 15 mm passenger side axle-differential bolts.
23. Turn steering wheel to far left.
24. Remove 6 15 mm drivers side axle-differential bolts.
25. Support axles with bungee cord to protect CV joints.
26. Loosen all differential bolts but do not remove (21 mm)
27. Support differential with transmission jack.
28. Remove the two long bolts from differential mount.
29. Remove the two short bolts supporting differential from frame.
30. Separate idler arm to center link bolt. This allows center link to rotate away from differential as you lower it. NOTE 1: Every video I've seen, people are disconnecting the tie rod end to do this. They are taking off too much here. NOTE 2: I have not actually done this yet. After lowering the differential, it is nicely resting on the center link. This is now lowered enough that I should have no trouble removing the oil pan. If I do, it is a matter of one bolt on the steering linkage, then the entire differential will come out.

That's where it stands for now. This actually took me 4 hours to do. Yes, I work really slowly, but part of it was figuring things out, part of it was documenting what I was doing, and part of it was working inefficiently. At first I jacked up only the front wheels, but I realized that to separate the front drive shaft I'd have to raise the rear as well so that the drive shaft would rotate.

Here are some things that may be completely unnecessary and a complete waste of time:

Raising the rear of the truck.
Releasing the boot clamp on the front drive shaft.
Separating the front drive shaft from the differential.

If I decide to remove the front differential, then yes, doing those three things would be necessary.

I'll come back to edit this later as I continue with the oil pan removal.

 

[latvius]

Raising the rear of the truck gives you more room underneath
boot clamp no, just extra work
Yes you have to disconnect front drive shaft so axle drops easy
I never removed/disconected anything steering related on either my 4wd tahoe or awd denali

Also you dont need to rotate the driveshaft, undo the u clamps and pry it back it is designed to move back and forth (extend and retract)

 

[Larryjb]

...
I never removed/disconected anything steering related on either my 4wd tahoe or awd denali

Also you dont need to rotate the driveshaft, undo the u clamps and pry it back it is designed to move back and forth (extend and retract)

Separating the center link from the pitman arm is only if I were to actually remove the differential. Did you remove the differential without disconnecting anything steering related?

 

[Rocket Man]

Why did you drain the front diff and unbolt the axles? It will drop down far enough without doing that. All I did with it was remove the drive shaft and unbolt it from the frame. When I pulled the pan I pried down on it a bit.

 

[Larryjb]

Even for me, it takes 10 minutes to unbolt the axles. This way you get more room without having to pry, allowing you to use two hands to manipulate the oil pan. Also, I saw the videos of people trying to pry the axle down. I've heard you have to be really careful with the CV joints so I didn't want to take any chances messing those up. Thirdly, unbolting the axles allows the differential to drop down lower, giving you more room to fit the pan in.

Obviously, you don't have to do this. For me, 10 minutes of extra work will probably protect the neighbourhood from learning some new words.

I drained the front differential because that one is super easy and I've never done it yet. The rear diff is messier, and requires that you clean more gasket surfaces. I may run out of time before I can get to changing the rear diff this time. I also have to save time to change my parking brake shoes.